cnc turning (bridgeport)

CNC LATHE MACHINE

MECHANICAL ENGINEERING DEPARTMENT

JHBO

PENGENALAN

CNC turning adalah bermula dengan penghasilan mesin

larik.

Menggunakan mesin larik untuk kerja-kerja melarik,menggerek, mengerudi, membuat

benang skru dan sebagainya.

• Numerical Control• 1950 - 1975NC• Computer Numerical Control with integrated computer

• 1970CNC• FLEXIBLE MANUFACTURING SYSTEM• 1990FFS• Computer Aided Design / Drawing• 1958CAD• Computer Aided Design and Computer Aided Manufacturing

• 1975CAD / CAM

• Computer integrated manufacturing with planning, design and manufacturing

• 1989CIM

SEJARAH CNC LATHE / TURNING

Program ini mula dibangunkan pada awal tahun 1970 selepas program DNC yang sangat popular sebelum program ini.Keperluan system kawalan ini ialah memudahkan penyuntingan aturcara,menyediakan analisis diogrisis,mengawal pembuatan,menambah kawalan sesuatu perkakas secara ekonomi,dan kos bagi program ini adalah murah.

MESIN LARIK

MESIN LARIK KONVENSIONAL

PLPG – JPTK – FKIP – UNS

Mesin CNC vs Konvensional

PLPG – JPTK – FKIP – UNS

Bahagian-bahagian Mesin CNC Lathe

Chuck/Cekam

Controller

Rumah Alat/Tool turret

Motor Utama

Eretan memanjang

Paksi- Z

Lampu

Eretan melintang/paksi- X

JENIS-JENIS MESIN

MAKINO (JAPAN)NAKAMURA TOME SC-150M (JAPAN)

HAAS HSI-RP: 2 Pallet Horizontal Machining Center

CNC MAZAK (JAPAN)

PEMBUANGAN TATAL @ PENYEJUK

CONTOL PANEL (PAPAN KAWALAN)

BAHAGIAN CONTROL PANEL

A) POWER OFF

B) POWER ON

C) CYCLE START

D) FEED HOLD

E) FEED RATE CONTROL

F) PANEL HAND WHEEL

G) EMERGENCY STOP

JENIS - JENIS MATA ALAT

CENTER DRILLENDMILL KARBIDA

GAMBARAJAH MATA ALAT JENIS ‘CARBIDA’

CNC PROGRAMMING

Defination

Part program is a set of instructions which instructs the machine tool about the processing steps to be performed for the manufacture of a component.

Part programming is the procedure by which the sequence of processing steps and other related data, to be performed on the CNC machine is planned and documented.

Some typical NC Words : N-Word (Sequence Number) :The first word in every block is the

sequence number.The sequence number is used to

identify the block. The sequence number is preceded

by word N and is written as N001, N005, etc.

Contoh G code

G00 rapid motionG01 line interpolation motionG02 CW interpolation motionG03 CCW interpolation motionG04 DwellG09 exact stopG10 set offsetG17 XY planeG18 ZX planeG19 YZ planeG20 select inchesG21 select metricG28 return to reference pointG29 return from reference pointG81 drill cycleG82 counter bore cycleG83 deep hole drilling cycleG90 absolute positionG91 INCREAMENTAL positionG99 rapid to retract plane

CONTOH PROJEK (SIMULASI)

MENGGUNAKAN PERKAKASAN EXSL - WIN

Contoh Arahan Kod :0300; N10 G97 G96 S2000 T0101 M3; N20 G00 X52 Z2; N30 G71 U0.3 R2; N40 G71 P50 Q110 U0.1 W0.1 F0.1; N50 G01 X20; N55 G01 Z0; N60 G01 X20 Z-15; N70 G02 X30 Z-20 R5; N80 G01 X40 Z-30; N90 G01 X40 Z-40; N100 G03 X50 Z-45 R5; N110 G01 X50 Z-70; N120 G70 P50 Q110 T0202 F0.1; N130 G28 U0 W0; M05; M30;

Turning Center Coordinate System

Z is the length of the part.

X is the diameter of the part.

The partially shaded circlerepresents the origin.

The programmer chooses thelocation of the origin on the part,usually the back, center or front,center.

We will always use the back,center since it simplifies machineset-up.

Program to move the tool, notthe work.

Incremental vs.Absolute Programming

Suppose we want to move from the origin

through points A, B, C, D, and E. We can move:

incrementally – distance from previous point,

or absolutely – new distance from the

origin

E

B

A

Point

Incremental Absolute

Z X Z X

Origin 0 0 0 0

A 1 1 1 1

B 2 0 3 1

C 0 1 3 2

D 2 0 5 2

E 1 4 6 6

Incremental vs.Absolute Programming

CD

M-CODESistem kod M mengawal keseluruhan mesin, menyebabkan ia berhenti,bermula, memasang pendingin (coolant), dan sebagainya.

Alatan mesin yang berbeza boleh menggunakan kod yang sama untuk melaksanakan fungsi yang berbeza, walaupun mesin yang mengunakan pengawal CNC yang sama.

Contoh arahan menggunakan kod M: Arahan membuka pelincir Arahan pergerakan pusingan ikut jam atau lawan

jam bagi alat pemotong

Contoh M Code

M00 program stopM01 optional program stopM02 program endM03 spindle on clockwiseM04 spindle on counter clockwiseM05 spindle stopM06 tool changeM08 coolant onM09 coolant off M10 clamps onM11 clamps offM30 end of program, reset to start

G-CODE

G-code adalah nama yang digunakan bagi bahasa pengaturcaraan yang mengawal mesin dan memberitahu peralatan mesin jenis kerja yang perlu dilakukan, contohnya :

Pergerakan yang cepat Satu siri pergerakan suapan Mengawal pergerakan suapan dalam

garis lurus atau lengkungan

Common Fanuc G Codes

Code Description

G00 Rentasan deras (titik ke titik)

G01 Suapan dalam gerakan lelurus

G02 Penentu dalaman membulat bagi lengkok ikut jam

G03 Penentu dalaman membulat bagi lengkok lawan jam

G20 Pemprograman dalam inci

G21 Pemprograman dalam inci

G28 Kembali kepada kedudukan asal

G 00 – LINEAR INTERPOLATION IN RAPID TRAVERSE

G 01 – LINEAR INTERPOLATION IN SLOW MOTION

G 02 – CIRCULAR INTERPOLATION (CW)

G 03 – CIRCULAR INTERPOLATION (CCW)

G 33 -THREAD CUTTING / TAPER THREAD CUTTING

G 71 - LONGITUDINAL STRAIGHT ROUGHING CYCLE

G 72 - CROSS ROUGHING CYCLE

G 74 - PECK DRILLING CYCLE

G 75 – GROOVING CYCLE

M00 programmed stop M01 optional stop M02 program end M30 program end with resetting

M03 activate spindle in clockwise rotation M04 activate spindel in counter - clockwise rotation M05 deactivate spindle

M08 activate coolant M09 deactivate coolant

M48 activate feedrate override dial M49 cancel feedrate override dial

M41 select lower spindle speed range M42 select higher spindle speed range

“M” CODE

PART PROGRAMMING

G01 – LINEAR INTERPOLATION

X Z

a 0 0

b 40 0

c 40 -40

d 80 -40

e 80 -90

f 110 -90

g 110 -140

G01 – LINEAR INTERPOLATION

N G X Z

N10 G00 50 1

N20 G01 50 -25

N30 G01 75 -25

N40 G01 100 -75

N50 G01 100 -100

N60 G01 101 -100

EXCERCISE 1

N G X Z

EXCERCISE 1- RESULT

N G X ZN10 G00 25 1

N20 G01 25 -12.5

N30 G01 37.5

-25

N40 G01 50 -25

N50 G01 50 -50

N60 G01 75 -62.5

N70 G01 75 -75

N80 G01 100 -87.5

N90 G01 100 -100

N100

G01 101 -100

EXCERCISE 2

N G X Z I K R

N10

N20

N30

N40

N50

N60

N70

N80

N90

EXCERCISE 2 - RESULT

N G X Z I K R

N10

G00

25 1

N20

G01

25 -25

N30

G02

50 -37.5

25 0

N40

G01

50 -50

N50

G02

75 -62.5

25 0

N60

G01

75 -75

N70

G03

100

-87.5

0 -12.5

N80

G01

100

-100

N90

G01

101

-100

CNC Turning Operation Procedure

Planning and ProgrammingTo program a CNC machine tool to create a part, you must follow a series of steps to be successful:

CNC Turning Operation Procedure

1. Examine the part drawing thoroughly and get a rough idea of how you want to proceed.

CNC Turning Operation Procedure

2. Figure out how to hold the raw material so you can perform as much machining as possible in one setup.

CNC Turning Operation Procedure

3.Decide what cutters are necessary to perform thevarious operations.

CNC Turning Operation Procedure

4.Write down the exact sequence of operationsnecessary to machine the part, one cutter at a time.

CNC Turning Operation Procedure

5. Convert your sequence of operations into a program and simulate the program if possible

Notes on Turning Center G & M Codes

• Most machines only allow one M code per block.

• The tool code (T) is four digits – the first two for the tool number, the second two for the offset number. They are usually the same.

(ex: T0101 / T0202)• All alpha characters must be in

uppercase

Running a Program for the First Time

1. Install all cutters in the proper holders.2. Install the fixture or chuck on the machine and establish the WCS (Work Coordinate System)3. Set the cutter offsets.4. Simulate the program on the machine.5. Slow rapid traverse down as low as possible.6. Initiate the single step cycle with your hand on the E-stop button at all times.7. Carefully watch the operations, press the feed hold button to take notes for any corrections.8. Install a part and go to step 5.

PROJEK CNC TURNING

Lakarkan gambarajah projek anda menggunakan software CAD atau secara insani.

Ukuran maksima untuk projek Panjang tidak lebih 100 mm Diameter tidak lebih 30mm

Buat program secara insani menggunakan G code dan M code berdasarkan rekabentuk yang dilakarkan.

CONTOH REKABENTUK PROJEK

CONTOH PROGRAM

:0029;(BISHOP)N10 G97 S2000 M03 T0101;N20 G00 X40 Z1;N30 G71 U1 R2;N40 G71 P50 Q180 U0.5 W0.5 F1;N50 G01 X0 Z0;N60 G03 X2 Z-1 R2;N150 G03 X10 Z-7.5 R8.5;N160 G01 X9 Z-9;N170 G03 X10 Z-11 R2;N180 G01 X9 Z-15;N190 G01 X9 Z-18N200 G01 X13 Z-36N201 G01 X15 Z-36.5;N202 G01 X15 Z-37;N203 G02 X17 Z-38 R1;N204 G03 X21 Z-40 R2;N205 G01 X21 Z-43;

N206 G03 X23 Z-45 R2;N207 G02 X25 Z-47 R2;N208 G01 X25 Z-50;N209 G01 X25 Z-55;N210 G70 P50 Q 209 T0101 F0.5;N211 G28 U0 W0;N212 M05;N213 M30;

Length : 100mmDiameter: 25mm